High density interconnection printed circuit board PCB puts forward high requirements for defect free blind holes copper filling. Here, 5-amino-1,3,4-thiadiazole-2-mercaptan, a small molecular compound containing sulfur and nitrogen heterocycles, is proposed as a new leveling agent to try to meet the top-down blind holes filling of high-density interconnected printed circuit board (PCB). The cross-sectional images of blind holes captured by optical microscopy show that the selected heterocyclic compounds with small molecules containing nitrogen and sulfur have good leveling ability and can realize the top-down super filling of blind holes. The electrochemical measurements were used to analyze the inhibition behavior of the leveling agent on copper ion deposition and its interaction with other additives. An atomic force microscope (AFM) and X-ray diffractometer (XRD) were used to study the effect of inhibitors on the surface morphology and crystal structure of copper crystals. In addition, quantum chemistry calculations and molecular dynamics simulations also were used to analysis the structure-performance correlation (active sites) and adsorption energy of the leveler at the molecular level to further understand the function of the levelers in the electrolyte system. This work will be inspiring for discovering new and effective levelers in the future.

中文翻译：

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5-氨基-1,3,4-噻二唑-2-硫醇作为盲孔镀铜的新型整平剂：理论计算和电化学研究


高密度互连印刷电路板PCB对无缺陷盲孔填铜提出了很高的要求。这里提出了 5-氨基-1,3,4-噻二唑-2-硫醇，一种含有硫和氮杂环的小分子化合物，作为一种新的流平剂，试图满足高密度互连印刷电路板 （PCB） 自上而下的盲孔填充。光学显微镜拍摄的盲孔横截面图像表明，所选的含氮、含硫小分子杂环化合物具有良好的流平能力，可实现盲孔自上而下的超级填充。电化学测量用于分析流平剂对铜离子沉积的抑制行为及其与其他添加剂的相互作用。使用原子力显微镜 （AFM） 和 X 射线衍射仪 （XRD） 研究抑制剂对铜晶体表面形貌和晶体结构的影响。此外，量子化学计算和分子动力学模拟还用于分析分子水平上整平剂的结构-性能相关性（活性位点）和吸附能，以进一步了解整平剂在电解质系统中的功能。这项工作将对将来发现新的有效矫平器具有启发性。